Ramp, Lane Closures on Northbound, Southbound US-101 as Part of Marin Sonoma Narrows B7 Project in Marin County

Schedule: Monday, Jan. 12 through Friday, Jan. 16 from 9:30 p.m. until 6 a.m.

Marin County - Caltrans has scheduled ramp and lane closures for electrical work on Northbound and Southbound US-101 for the Marin Sonoma Narrows B7 project from Monday, Jan. 12 through Friday, Jan. 16 from 9:30 p.m. until 6 a.m. the next mornings.

The schedule for ramp closures is as follows:

Monday through Friday: The De Long Avenue on- and off-ramps on Northbound and Southbound US-101 are scheduled to be closed.

Thursday, Jan. 15: The Atherton Avenue off-ramp on Northbound US-101, and the Atherton Avenue on-ramp on Southbound US-101 are scheduled to be closed.

Lanes will be closed on Northbound and Southbound US-101 during the aforementioned days and times.

Work is weather dependent.

Detours for De Long on-ramp closures on US-101

• Northbound: Drivers should enter Southbound US-101 at De Long Avenue, exit at the Rowland Blvd off-ramp, turn left, and enter Northbound US-101
• Southbound: Drivers should travel Southbound on Redwood Boulevard and enter Southbound US-101 at Rowland Boulevard.

Detours for De Long off-ramp closures on US-101

• Northbound: De Long Avenue off-ramp closure: Drivers should exit at Atherton Avenue, turn left, and enter Southbound US-101 to get to the De Long off-ramp
• Southbound: De Long off-ramp closure: Drivers should exit at Atherton Avenue and then use Redwood Boulevard to reach De Long Avenue.

Detours for Atherton Avenue ramp closures on US-101

• Northbound off-ramp: Drivers should exit at San Antonio, turn left, and enter Southbound US-101 to get to the Atherton off-ramp.
• Southbound on-ramp: Drivers can enter Northbound US-101 at Atherton Avenue, exit at San Antonio Avenue and then enter back on Southbound US-101.

Construction for the project includes widening US-101 to install HOV lanes for 3.5 miles along the northbound lanes from North Novato to the Marin, Sonoma line, and for 6.3 miles along the southbound lanes from De Long Avenue to the county line.

This is the last remaining High Occupancy Vehicle (HOV) lane construction project as part of the 16-mile US-101 Marin-Sonoma Narrows (MSN) program. This project will complete and allow continuous HOV lanes on US-101 from Sausalito in Marin County to Windsor in Sonoma County.

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For real-time information, visit Caltrans QuickMap: https://quickmap.dot.ca.gov
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Or call 1-800-472-7623, 1-800-427-ROAD for state highway conditions statewide.